1. Field Of The Invention
The present invention relates to a positioning apparatus for a positioning head that can be moved in a guide plane, in particular for equipping electrical circuit boards with components, whereby a chassis of the positioning means comprises a linear guide that defines the x direction, in which an elongated bearer that extends transversely thereto can be moved by means of a drive, on which bearer the positioning head can be moved in the y direction.
2. Description of the Prior Art
An apparatus of this sort is known for example from U.S. Pat. No. 4,836,111. According to this reference, the bearer is guided on a guide rail of the chassis in a double bearing, which defines both the direction of motion and also the angular position of the carriage. A simple wheel-type support bearing on the opposite side serves for the simple support of the bearer on a support rail.
A drive unit is allocated to the double bearing, the unit driving the carriage in the direction of the linear guide. The transverse bearer is provided with a transverse guide on which a positioning head is movably mounted. This head is movable between a component supply and a processing location for the assembly, in order to transport components retrieved from the component supplies to their assembly location on the circuit board.
When the bearer is braked rapidly, transverse forces result from its inherent weight, as well as from the mass of the equipping head, which forces lead to an elastic excursion of the bearer in the x direction. These excursions correspond to the excursions given a crosspiece fixed at one side, and are particularly large at the unguided end. A component can be placed precisely only if the corresponding oscillations in the bearer have decayed sufficiently.